It is presently known to illuminate hanging works of art with a lighting fixture of particular design. These known lighting fixtures comprise a substantially semi-cylindrical shade/reflector within which one or more tubular incandescent bulbs reside. The fixture has an extending arm through which the wiring extends, and a perpendicular portion of the extending arm extends downward and is fixed by screws or the like to the back of the frame of the object to be illuminated. In this manner, the fixture extends above and a small distance out (e.g., four to twelve inches) from the plane of the object to be illuminated.
The picture lighting fixtures of the prior art have been in existence in their current state for more than fifty years and are non-optimal for several reasons: their reflectors are not carefully designed to evenly illuminate the entire object; the heat generated by the incandescent bulbs limits the choice of bulbs to those of relatively low power consumption; and their incandescent bulbs emit light of undesirable color. More particularly, in the typical known fixture, the reflector is not designed so much to distribute light evenly over the object illuminated as it is designed to shade the light from illuminating anything but the object. Moreover, the bulbs used in the known fixtures are most often twenty-five watt incandescent bulbs which emit a relative dim orange colored light and which are often insufficient to properly light a large artwork. If higher wattage bulbs are used, the light generated still will be orange-colored and unevenly distributed, and the heat generated may damage the object or objects to be illuminated.
It should be recognized that the illumination of works of art considerably influences human perception of the work, particularly with regard to color. Indeed, artists most typically paint in the daylight. Yet, to date, the lighting fixtures used to illuminate hanging works of art do not seriously address the issues of color temperature or diffusion.
Color temperature of illumination is an important consideration in the human perception of color in the object illuminated. Daylight has a color temperature of 6,500.degree.-12,000.degree. Kelvin which is paradoxically called a "cool" light since it is more in the blue spectrum. Typical incandescent bulbs have a color temperature of about 2,500.degree.-2700.degree. Kelvin and are paradoxically called "warm" lights since they are more in the red/orange spectrum. The lower the wattage of an incandescent bulb, the "warmer" its light.
Fluorescent bulbs, however, are capable of producing light with a temperature over 6,500.degree. Kelvin which is very close to daylight and allows the most accurate human perception of color and of the color which the artist intended. Moreover, modern fluorescent bulbs are available in a number of different color temperatures which are not dependent on the power consumption of the bulbs. Fluorescent bulbs also have the advantage of generating very little heat compared to incandescent bulbs of the same brightness. For example, a typical fifteen watt fluorescent bulb emits light having a brightness of 900 lumens. An incandescent bulb generating 900 lumens would require approximately sixty watts of power and would generate substantially more heat than a fifteen watt fluorescent bulb.
While it would be advantageous to provide evenly distributed fluorescent light for illuminating hanging art work given the advantages of color temperature, brightness, lower operating temperature and lower power consumption, fluorescent bulbs have not been used for this purpose because of the large ballasts required and because small, standard, thin fluorescent bulbs do not emit enough lumens. Recently, however, light bulb manufacturers have introduced families of fluorescent bulbs with integral or separate ballasts which screw into an incandescent bulb socket (e.g. Sylvania, Osram and Phillips). Also, "E-Lamp" bulbs which utilize high-frequency radio signals instead of a filament to produce light have been announced. The new fluorescent and E-lamp bulbs offer all of the advantages of the standard fluorescent bulbs with the necessary electronics built into an oversized base which is either an integral part of the bulb or with a base into which a bulb can be inserted. Unfortunately, however, these new type bulbs do not fit into existing lighting fixtures now used to illuminate hanging works of art.